[rfc] Do not read from the executable if ptrace fails

[Ulrich Weigand]

Daniel Jacobowitz wrote:

> > This used to work (probably accidentally?), but is broken by
> > this patch.  Any suggestions how to fix it?  Should the overlay
> > logic from xfer_memory be moved to memory_xfer_partial, maybe?
> 
> That sounds reasonable.  What about if we check for an unmapped
> overlay address at the same point we handle trust_readonly?

Like so?  Tested on spu-elf, fixes the overlay test case.

Bye,
Ulrich


ChangeLog:

	* target.c (memory_xfer_partial): Accesses to unmapped overlay
	sections should always go to the executable file.

Index: gdb/target.c
===================================================================
RCS file: /cvs/src/src/gdb/target.c,v
retrieving revision 1.144
diff -c -p -r1.144 target.c
*** gdb/target.c	1 Jul 2007 22:35:55 -0000	1.144
--- gdb/target.c	23 Jul 2007 20:39:33 -0000
*************** memory_xfer_partial (struct target_ops *
*** 1017,1022 ****
--- 1017,1030 ----
  	return xfer_memory (memaddr, readbuf, len, 0, NULL, ops);
      }
  
+   /* Likewise for accesses to unmapped overlay sections.  */
+   if (readbuf != NULL && overlay_debugging)
+     {
+       asection *section = find_pc_overlay (memaddr);
+       if (pc_in_unmapped_range (memaddr, section))
+ 	return xfer_memory (memaddr, readbuf, len, 0, NULL, ops);
+     }
+ 
    /* Try GDB's internal data cache.  */
    region = lookup_mem_region (memaddr);
    /* region->hi == 0 means there's no upper bound.  */


-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com